malkia parent
In case someone is curious about how the 48-bit virtual space is split here is good info - https://wiki.osdev.org/Page_Tables#Long_mode_(64-bit)_page_m...
That's for amd64/x86_64. macOS, iOS, and recently Android on ARM64 use 16KB pages. Though, Windows does seem to use 4KB pages: https://devblogs.microsoft.com/oldnewthing/20210510-00/?p=10...
Huh. It'd never occured to me that Alpha/AXP was the only NT port that doesn't use 4KB pages (EDIT: and Itanium...). That's interesting -- I wonder how they dealt with that, especially with 16/32-bit x86 emulation (fx!32, good enough that it runs ClassiCube and Half-Life), and the dot net port that never saw the light of day, but was evidently worked on (there's still evidence of the AXP64 port in the open source dotnet, and evidence for an AXP port floating around elsewhere on GitHub...)
I know on PowerPC, with 64KB pages, IBM (?) added the subpage_prot syscall to Linux for emulation of 4KB pages, for the sake of their x86 emulation software.
Really, it's weird that NT apparently has/had some architectural support for larger pages, and then never used it again...
There is one paragraph showing when 4kb pages are used, and 4 level deep directories. (PML4 -> PDP ->